Tests.

test/CMakeLists.txt

@@ -83,6 +83,8 @@ set(libsolidity_sources
     libsolidity/InlineAssembly.cpp
     libsolidity/LibSolc.cpp
     libsolidity/Metadata.cpp
+    libsolidity/MemoryGuardTest.cpp
+    libsolidity/MemoryGuardTest.h
     libsolidity/SemanticTest.cpp
     libsolidity/SemanticTest.h
     libsolidity/SemVerMatcher.cpp

test/InteractiveTests.h

@@ -22,6 +22,7 @@
 #include <test/libsolidity/ABIJsonTest.h>
 #include <test/libsolidity/ASTJSONTest.h>
 #include <test/libsolidity/GasTest.h>
+#include <test/libsolidity/MemoryGuardTest.h>
 #include <test/libsolidity/SyntaxTest.h>
 #include <test/libsolidity/SemanticTest.h>
 #include <test/libsolidity/SMTCheckerTest.h>
@@ -74,6 +75,7 @@ Testsuite const g_interactiveTestsuites[] = {
 	{"JSON ABI",               "libsolidity", "ABIJson",               false, false, &ABIJsonTest::create},
 	{"SMT Checker",            "libsolidity", "smtCheckerTests",       true,  false, &SMTCheckerTest::create},
 	{"Gas Estimates",          "libsolidity", "gasTests",              false, false, &GasTest::create},
+	{"Memory Guard Tests",     "libsolidity", "memoryGuardTests",     false, false, &MemoryGuardTest::create},
 	{"Ewasm Translation",      "libyul",      "ewasmTranslationTests", false, false, &yul::test::EwasmTranslationTest::create}
 };
 

test/cmdlineTests/constant_optimizer_yul/output

@@ -11,22 +11,23 @@ object "C_12" {
     code {
         {
             /// @src 0:61:418  "contract C {..."
-            mstore(64, 128)
+            let _1 := memoryguard(0x80)
+            mstore(64, _1)
             if callvalue() { revert(0, 0) }
             /// @src 0:103:238  "assembly {..."
             sstore(0, shl(180, 1))
             /// @src 0:61:418  "contract C {..."
-            let _1 := datasize("C_12_deployed")
-            codecopy(128, dataoffset("C_12_deployed"), _1)
-            return(128, _1)
+            let _2 := datasize("C_12_deployed")
+            codecopy(_1, dataoffset("C_12_deployed"), _2)
+            return(_1, _2)
         }
     }
     /// @use-src 0:"constant_optimizer_yul/input.sol"
     object "C_12_deployed" {
         code {
             {
                 /// @src 0:61:418  "contract C {..."
-                mstore(64, 128)
+                mstore(64, memoryguard(0x80))
                 if callvalue() { revert(0, 0) }
                 /// @src 0:279:410  "assembly {..."
                 sstore(0, 0x1000000000000000000000000000000000000000000000)

test/cmdlineTests/ir_with_assembly_no_memoryguard_creation/input.sol

@@ -3,6 +3,6 @@ pragma solidity >=0.0.0;
 pragma abicoder v2;
 
 contract D {
-    constructor() { assembly {}}
+    constructor() { assembly { mstore(0,0) } }
     function f() public pure {}
 }

test/cmdlineTests/ir_with_assembly_no_memoryguard_creation/output

@@ -10,9 +10,12 @@ Optimized IR:
 object "D_12" {
     code {
         {
-            /// @src 0:82:161  "contract D {..."
+            /// @src 0:82:175  "contract D {..."
             mstore(64, 128)
             if callvalue() { revert(0, 0) }
+            /// @src 0:115:139  "assembly { mstore(0,0) }"
+            mstore(0, 0)
+            /// @src 0:82:175  "contract D {..."
             let _1 := datasize("D_12_deployed")
             codecopy(128, dataoffset("D_12_deployed"), _1)
             return(128, _1)
@@ -22,7 +25,7 @@ object "D_12" {
     object "D_12_deployed" {
         code {
             {
-                /// @src 0:82:161  "contract D {..."
+                /// @src 0:82:175  "contract D {..."
                 let _1 := memoryguard(0x80)
                 mstore(64, _1)
                 if iszero(lt(calldatasize(), 4))

test/cmdlineTests/ir_with_assembly_no_memoryguard_runtime/input.sol

@@ -4,6 +4,6 @@ pragma abicoder v2;
 
 contract D {
     function f() public pure {
-        assembly {}
+        assembly { mstore(0,0) }
     }
 }

test/cmdlineTests/ir_with_assembly_no_memoryguard_runtime/output

@@ -10,7 +10,7 @@ Optimized IR:
 object "D_8" {
     code {
         {
-            /// @src 0:82:153  "contract D {..."
+            /// @src 0:82:166  "contract D {..."
             let _1 := memoryguard(0x80)
             mstore(64, _1)
             if callvalue() { revert(0, 0) }
@@ -23,7 +23,7 @@ object "D_8" {
     object "D_8_deployed" {
         code {
             {
-                /// @src 0:82:153  "contract D {..."
+                /// @src 0:82:166  "contract D {..."
                 mstore(64, 128)
                 if iszero(lt(calldatasize(), 4))
                 {
@@ -32,6 +32,8 @@ object "D_8" {
                     {
                         if callvalue() { revert(_1, _1) }
                         if slt(add(calldatasize(), not(3)), _1) { revert(_1, _1) }
+                        /// @src 0:134:158  "assembly { mstore(0,0) }"
+                        mstore(/** @src 0:82:166  "contract D {..." */ _1, _1)
                         return(128, _1)
                     }
                 }

test/libsolidity/MemoryGuardTest.cpp

@@ -0,0 +1,78 @@
+/*
+	This file is part of solidity.
+
+	solidity is free software: you can redistribute it and/or modify
+	it under the terms of the GNU General Public License as published by
+	the Free Software Foundation, either version 3 of the License, or
+	(at your option) any later version.
+
+	solidity is distributed in the hope that it will be useful,
+	but WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+	GNU General Public License for more details.
+
+	You should have received a copy of the GNU General Public License
+	along with solidity.  If not, see <http://www.gnu.org/licenses/>.
+*/
+// SPDX-License-Identifier: GPL-3.0
+
+#include <test/libsolidity/MemoryGuardTest.h>
+
+#include <test/libyul/Common.h>
+#include <libsolidity/codegen/ir/Common.h>
+#include <libsolutil/Algorithms.h>
+#include <libyul/Object.h>
+#include <libyul/backends/evm/EVMDialect.h>
+#include <libyul/optimiser/FunctionCallFinder.h>
+#include <fstream>
+#include <memory>
+#include <stdexcept>
+
+using namespace std;
+using namespace solidity;
+using namespace solidity::util;
+using namespace solidity::util::formatting;
+using namespace solidity::langutil;
+using namespace solidity::frontend;
+using namespace solidity::frontend::test;
+using namespace yul;
+
+TestCase::TestResult MemoryGuardTest::run(ostream& _stream, string const& _linePrefix, bool _formatted)
+{
+	compiler().reset();
+	compiler().setSources(StringMap{{"", m_source}});
+	compiler().setViaIR(true);
+	compiler().setOptimiserSettings(OptimiserSettings::none());
+	if (!compiler().compile())
+		return TestResult::FatalError;
+
+	m_obtainedResult.clear();
+	for (string contractName: compiler().contractNames())
+	{
+		ErrorList errors;
+		auto [object, analysisInfo] = yul::test::parse(
+			compiler().yulIR(contractName),
+			EVMDialect::strictAssemblyForEVMObjects({}),
+			errors
+		);
+
+		if (!object || !analysisInfo || Error::containsErrors(errors))
+		{
+			AnsiColorized(_stream, _formatted, {formatting::BOLD, formatting::RED}) << _linePrefix << "Error parsing IR." << endl;
+			return TestResult::FatalError;
+		}
+
+		auto handleObject = [&](std::string const& _kind, Object const& _object) {
+			m_obtainedResult += contractName + "(" + _kind + ") " + (FunctionCallFinder::run(
+				*_object.code,
+				"memoryguard"_yulstring
+			).empty() ? "false" : "true") + "\n";
+		};
+		handleObject("creation", *object);
+		size_t deployedIndex = object->subIndexByName.at(
+			YulString(IRNames::deployedObject(compiler().contractDefinition(contractName)))
+		);
+		handleObject("runtime", dynamic_cast<Object const&>(*object->subObjects[deployedIndex]));
+	}
+	return checkResult(_stream, _linePrefix, _formatted);
+}

test/libsolidity/MemoryGuardTest.h

@@ -0,0 +1,53 @@
+/*
+	This file is part of solidity.
+
+	solidity is free software: you can redistribute it and/or modify
+	it under the terms of the GNU General Public License as published by
+	the Free Software Foundation, either version 3 of the License, or
+	(at your option) any later version.
+
+	solidity is distributed in the hope that it will be useful,
+	but WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+	GNU General Public License for more details.
+
+	You should have received a copy of the GNU General Public License
+	along with solidity.  If not, see <http://www.gnu.org/licenses/>.
+*/
+// SPDX-License-Identifier: GPL-3.0
+
+#pragma once
+
+#include <test/libsolidity/AnalysisFramework.h>
+#include <test/TestCase.h>
+#include <test/CommonSyntaxTest.h>
+#include <liblangutil/Exceptions.h>
+#include <libsolutil/AnsiColorized.h>
+
+#include <iosfwd>
+#include <string>
+#include <vector>
+#include <utility>
+
+namespace solidity::frontend::test
+{
+
+using solidity::test::SyntaxTestError;
+
+class MemoryGuardTest: public AnalysisFramework, public TestCase
+{
+public:
+	static std::unique_ptr<TestCase> create(Config const& _config)
+	{
+		return std::make_unique<MemoryGuardTest>(_config.filename);
+	}
+	MemoryGuardTest(std::string const& _filename): TestCase(_filename)
+	{
+		m_source = m_reader.source();
+		m_expectation = m_reader.simpleExpectations();
+	}
+
+	TestResult run(std::ostream& _stream, std::string const& _linePrefix = "", bool _formatted = false) override;
+};
+
+}

test/libsolidity/memoryGuardTests/constructor_safe_deploy_unsafe.sol

@@ -0,0 +1,17 @@
+contract C {
+    constructor() {
+        uint256 x;
+        assembly { x := 0 }
+        f();
+    }
+    function f() internal pure {
+        /// @solidity memory-safe-assembly
+        assembly { mstore(0, 0) }
+    }
+    function g() public pure {
+        assembly { mstore(0, 0) }
+    }
+}
+// ----
+// :C(creation) true
+// :C(runtime) false

test/libsolidity/memoryGuardTests/constructor_unsafe_deploy_safe.sol

@@ -0,0 +1,17 @@
+contract C {
+    constructor() {
+        uint256 x;
+        assembly { x := 0 }
+        f();
+    }
+    function f() internal pure {
+        assembly { mstore(0, 0) }
+    }
+    function g() public pure {
+        /// @solidity memory-safe-assembly
+        assembly { mstore(0, 0) }
+    }
+}
+// ----
+// :C(creation) false
+// :C(runtime) true

test/libsolidity/memoryGuardTests/free_function.sol

@@ -0,0 +1,29 @@
+function safe() pure returns (uint256 x) {
+    assembly { x := 42 }
+    /// @solidity memory-safe-assembly
+    assembly { mstore(0, 0) }
+}
+function unsafe() pure returns (uint256 x) {
+    assembly { pop(mload(0)) }
+}
+contract C {
+    constructor() {
+        unsafe();
+    }
+    function f() public pure {
+        safe();
+    }
+}
+contract D {
+    constructor() {
+        safe();
+    }
+    function f() public pure {
+        unsafe();
+    }
+}
+// ----
+// :C(creation) false
+// :C(runtime) true
+// :D(creation) true
+// :D(runtime) false

test/libsolidity/memoryGuardTests/multi_annotation.sol

@@ -0,0 +1,17 @@
+contract C {
+    constructor() {
+        /// @solidity memory-safe-assembly    a memory-safe-assembly
+        assembly { mstore(0, 0) }
+    }
+    function f() internal pure {
+        /// @solidity a memory-safe-assembly
+        assembly { mstore(0, 0) }
+        /// @solidity a
+        ///           memory-safe-assembly
+        ///           b
+        assembly { mstore(0, 0) }
+    }
+}
+// ----
+// :C(creation) true
+// :C(runtime) true

test/libsolidity/memoryGuardTests/multiple_contracts.sol

@@ -0,0 +1,25 @@
+contract C {
+    constructor(uint256 x) {
+        assembly { x := 4 }
+        /// @solidity memory-safe-assembly
+        assembly { mstore(0, 0) }
+    }
+    function f() public pure {
+        assembly { mstore(0,0) }
+    }
+}
+contract D {
+    constructor() {
+        assembly { mstore(0,0) }
+    }
+    function f(uint256 x) public pure {
+        assembly { x := 4 }
+        /// @solidity memory-safe-assembly
+        assembly { mstore(0, 0) }
+    }
+}
+// ----
+// :C(creation) true
+// :C(runtime) false
+// :D(creation) false
+// :D(runtime) true

test/libsolidity/memoryGuardTests/safe_and_unmarked_empty.sol

@@ -0,0 +1,10 @@
+contract C {
+    function f() external pure {
+        /// @solidity memory-safe-assembly
+        assembly {}
+        assembly {}
+    }
+}
+// ----
+// :C(creation) true
+// :C(runtime) true

test/libsolidity/memoryGuardTests/safe_and_unmarked_unsafe.sol

@@ -0,0 +1,10 @@
+contract C {
+    function f() external pure {
+        /// @solidity memory-safe-assembly
+        assembly {}
+        assembly { mstore(0,0) }
+    }
+}
+// ----
+// :C(creation) true
+// :C(runtime) false

test/libsolidity/memoryGuardTests/stub.sol

@@ -0,0 +1,4 @@
+contract C {}
+// ----
+// :C(creation) true
+// :C(runtime) true

test/libsolidity/memoryGuardTests/unmarked_but_no_memory_access.sol

@@ -0,0 +1,8 @@
+contract C {
+    function f(uint256 x, uint256 y) public pure returns (uint256 z){
+        assembly { z := add(x, y) }
+    }
+}
+// ----
+// :C(creation) true
+// :C(runtime) true